NYC-WTC_000202171

NYC 9/11 Public Portal Document

(SSKTC 104 East 25th St., 10th Fi New York, New York 10010 www.atc-enviro.com 212.3B3.8280 Fax 212.353.8306 ASSOCIATES INC.

August 29, 2002

Mr. Bernard P. Orlan Director, Environmental Health and Safety New York City Department of Education 28-11 Queens Plaza North Long Island City, NY 11101

Re: Air Sampling for Hydrocarbons P.S. 89M: ATC Project No. 15-19125-0297

Dear Mr. Orlan;

ATC Associates, Inc. (ATC) is pleased to provide this report of the results of air sampling for volatile hydrocarbon compounds conducted on August 16, 2002, at the referenced school. The New York City Department of Education (DOE) requested this sampling to verify that acceptable indoor air quality i.s being maintained.

Scope of Work

ATC collected four (4) samples for hydrocarbon compounds (HC) at specified locations. Samples were collected for ten (10) hours using activated coconut shell charcoal tubes connected to battery-powered sampling pumps at a flow rate of 0.2 liters per minute. Pumps were calibrated before and after each sampling period. Three (3) samples were collected from locations outside the building and one (1) was collected inside. One blank tube was also submitted. The samples were sent to PSC Analytical Services, Inc., an American Industrial Hygiene Association- accredited laboratory in Reading, PA. Analysis was performed by capillary gas chromatography/flame ionization detection (OSHA Method 7),

Wagdi Abdelshahid and Tenzin Namgyal, Industrial Hygienists from ATC’s New York City office, conducted, the sampling consistent with accepted industrial hygiene practices. The results represent conditions on the day the samples were collected!

Each sample was analyzed for a panel of sixteen (16) specific HC compounds. These compounds were; pentane, acetone, methylene chloride, hexane, chloroform, methyl chloroform, benzene, 1,2-di chloroethane, trichloroethylene, toluene, perchloroetyhylene (tetrachloroethylene), chlorobenzene, ethylbenzene, styrene, cumene and xylenes. In addition, two non-identified . peaks, total other A-hydrocarbons and total other B-hydrocarbons, were reported. The A- hydrocarbons are those, such as gasoline or light alcohols, with boiling points less than that of benzene (176°F). The B-hydrocarbons are those, such as mineral spirits or petroleum naphtha, with boiling points greater than that of benzene. A copy of the analytical laboratory report is attached.

CITY_21MC100_003270380

NYC-WTC_000202171